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0.17.0-bin-SNAPSHOT

Deprecated: Nonlocal Returns

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Returning from nested anonymous functions has been deprecated. Nonlocal returns are implemented by throwing and catching scala.runtime.NonLocalReturnException-s. This is rarely what is intended by the programmer. It can be problematic because of the hidden performance cost of throwing and catching exceptions. Furthermore, it is a leaky implementation: a catch-all exception handler can intercept a NonLocalReturnException.

A drop-in library replacement is provided in scala.util.control.NonLocalReturns:

import scala.util.control.NonLocalReturns._

returning { ... throwReturn(x) ... }